﻿using System;
using System.Collections.Generic;
using System.Text;
using System.Xml.Serialization;

namespace Ch.Admin.Bfs.Sms.Sdmx.Utils
{
    /// <summary>
    /// For some reason, the generic Dictionary in .net 2.0 is not XML serializable.  
    /// The following code snippet is a xml serializable generic dictionary.  
    /// The dictionary is serialzable by implementing the IXmlSerializable interface.  
    /// </summary>
    [XmlRoot("dictionary")]
    public class SerializableDictionary<TKey, TValue> : Dictionary<TKey, TValue>, IXmlSerializable
    {
        #region Constants

        const string ITEM_TAG = "item";
        const string KEY_TAG = "key";
        const string VALUE_TAG = "value";

        #endregion

        #region C'tors

        public SerializableDictionary()
            : base()
        {
        }
        public SerializableDictionary(IDictionary<TKey, TValue> dictionary)
            : base(dictionary)
        {
        }
        #endregion

        #region IXmlSerializable Members

        public System.Xml.Schema.XmlSchema GetSchema()
        {
            return null;
        }

        public void ReadXml(System.Xml.XmlReader reader)
        {
            XmlSerializer keySerializer = new XmlSerializer(typeof(TKey));
            XmlSerializer valueSerializer = new XmlSerializer(typeof(TValue));

            bool wasEmpty = reader.IsEmptyElement;
            reader.Read();

            if (wasEmpty)
                return;

            while (reader.NodeType != System.Xml.XmlNodeType.EndElement)
            {
                reader.ReadStartElement(ITEM_TAG);

                reader.ReadStartElement(KEY_TAG);
                TKey key = (TKey)keySerializer.Deserialize(reader);

                reader.ReadEndElement();

                reader.ReadStartElement(VALUE_TAG);
                TValue value = (TValue)valueSerializer.Deserialize(reader);
                reader.ReadEndElement();

                this.Add(key, value);

                reader.ReadEndElement();
                reader.MoveToContent();

            }
            reader.ReadEndElement();
        }



        public void WriteXml(System.Xml.XmlWriter writer)
        {
            XmlSerializer keySerializer = new XmlSerializer(typeof(TKey));
            XmlSerializer valueSerializer = new XmlSerializer(typeof(TValue));

            foreach (TKey key in this.Keys)
            {
                writer.WriteStartElement(ITEM_TAG);

                writer.WriteStartElement(KEY_TAG);
                keySerializer.Serialize(writer, key);
                writer.WriteEndElement();

                writer.WriteStartElement(VALUE_TAG);
                TValue value = this[key];
                valueSerializer.Serialize(writer, value);

                writer.WriteEndElement();

                writer.WriteEndElement();
            }
        }

        #endregion

    }
}

